Chapter 02 - Transmission Media in Compter Network 2026 - ShaileshSrn

Transmission Media

What is Transmission Media? 

Ans : Transmission Media is the communication path through which data travels from one device to another in a computer network. 

When you send a message, browse a website, watch a YouTube, a transfer files, the data travels through a transmission medium. 

Simple:  TM is the physical or wireless path used to transmit data signals between networks devices.

 

Why Transmission Media is Important?   

Ans :Simple without transmission media, device cannot communicate with each other. 

It helps in: 

• Data transmission 
• Internet Communication
• Resource sharing
• Voice and video communication
• Network connectivity

 

Types of Transmission Media?    

Transmission media is divided into two types categories:  

1. Guided Media:
1. Twisted Pair Cable
2. Coaxial Cable
3. Optical Fiber Cable  
2. Unguided Media: 
1. Radio Waves
2. Microwaves
3. Infrared
4. Satellite Communication

 

1. Guided Media(Wired Transmission)   

Guided media uses a physical cable to transmit data. 

 1. Twisted Pair Cable: TP cable consists of two insulated copper wires twisted together. The twisting helps reduce electromagnetic interference and signal noise.

Types of Twisted Pair Cable:

1. UTP (UnShielded Twisted Pair):
2. STP (Shielded Twisted Pair):

 Both Cable Where Can I Used:

• Home networking
• Office LAN
• Telephone systems
• Ethernet Networks

 Advantages: 

• Cheap
• Easy installation
• Flexible
• Widely available 

DisAdvantages: 

• Limited distance
• Affected by noise
• Lower speed than fiber optics

  2. Coaxial Cable: A Coaxial cable contains central copper conductor, insulation layer, Metallic shield, Outer protective cover. 

Outer Jacket > Shield Layer > Insulator > Capper Core

How it works: Electrical signals travel through the central conductor while the metallic shield protects against interference. 

Application: 

• Cable 
• CCTV
• Broadband Internet
• Radio transmission

Advantages:  

• Better noise protection
• Higher bandwidth than twisted pair
• More reliable 

Disadvantages:  

• More expensive
• Difficult installation
• Less Flexible 

 

3. Optical Fiber Cable: Optical Fiber transmits data using light instead of electricity, It is made of very thin glass or plastic fibers.  

Structure:  Outer jacket > Cladding > Core(Light Travels Here)  

Working Principle: Uses a phenomenon called: 

Total Internal Reflection: Light enter the fiber and continuously reflect inside the core until it reaches the destination.

Types of Fiber Optic Cable: 

Single Mode Fiber (SMF):

• Very long distance
• High Speed
• Used by telecom companies  

 Multi Mode Fiber (SMF):

• Short distance
• Lower Cost
• Used inside buildings 

Application: 

• High-Speed Internet
• Data Centers 
• Cloud Infrastructure
• Submarine Internet Cables
• Telecommunications 

Advantages:  

• Extremely High Speed
• Long Distance communication
• No electromagnetic Interference
• Highly secure

Disadvantages:  

• Expensive
• Difficult to repair 
• Specialized Installations required

 

2. Unguided Media(Wireless Transmission) :   

 Unguided media transmits data through air without cables so read below mentions points this very helpful for you maybe: 

 1. Radio Waves: Radio waves are electromagnetic waves used for wireless communication. 

Frequency Range: 

Approximately: 3 Khz - 1 Ghz

Application: 

• Wi-Fi
• RM Radio
• Mobile Network
• Bluetooth

Advantages:  

• No Wires needed
• Covers larger areas
• Easy deployment

Disadvantages:  

• Interference
• Security Concerns
• Signal weakening

2. Microwaves:- Microwaves are high - frequency radio waves used for long distance communication. 

So microwave communication requires, Line of Sight Both transmitting and receiving antennas must directly face other. 

Application: 

• Mobile Towers
• Satellite Links 
• TV Broadcasting
• Internet Backbone Networks  

Advantages: 

• High bandwidth
• Long distance
• Faster communication 

Disadvantage: 

• Weather affects signals
• Requires clear path
• Costly equipment

 3. Infrared Communication:- Infrared uses infrared waves for short - range communication. 

 Applications: 

• TV Remote Controls
• Wireless Mouse 
• Sensors 
• Security Systems

Advantage: 

• Low Cost
• Secure
• Simple Implementations   

Disadvantage: 

• Very Short range
• Cannot pass through walks
• Requires direct alignment

4. Satellite Communication: SC uses artificial satellite orbiting Earth to transmit signals

 Status:  Sender > Ground Station > Satellite > Ground Station > Reciver

Applications: 

• GPS Navigation
• Television Broadcasting
• Military Communication
• Weather Monitoring
• International Communication

Advantage: 

• Global Coverage 
• Remote area connectivity
• Reliable communication

Disadvantage: 

• Expensive
• Signal delay
• Weather impact

 

Real - World Example

• Technology          -     Transmission Media Used

• Office LAN         -         Twisted Pair Cable  
• Broadband Internet      - Fiber Optic 
• Mobile Network         -         Microwaves and Radio Waves
• Wi-fi             - Radio Waves
• TV Remote             --         Infrared
• GPS             -- Satellite Communication 

 

 

 

Hope this articles is helpful for you and read more for best way. Thank You.